In recent years, secondary batteries, which can be charged and discharged, have been widely used as an energy source for wireless mobile devices. In addition, such secondary batteries have attracted considerable attention as an energy source for electric vehicles and hybrid electric vehicles, which have been developed to solve problems, such as air pollution, caused by existing gasoline and diesel vehicles using fossil fuel. Therefore, secondary batteries are being applied to an increasing number of applications owing to advantages thereof and, in the future, secondary batteries are expected to be applied to even more applications and products.
Based on the construction of electrodes and an electrolytic solution, secondary batteries may be classified into a lithium ion battery, a lithium ion polymer battery, and a lithium polymer battery. In particular, the lithium ion polymer battery has been increasingly used because the lithium ion polymer battery has a low possibility of leakage of an electrolytic solution and can be easily manufactured. Based on the shape of a battery case, on the other hand, secondary batteries may also be classified into a cylindrical battery having an electrode assembly mounted in a cylindrical metal container, a prismatic battery having an electrode assembly mounted in a prismatic metal container, and a pouch-shaped battery having an electrode assembly mounted in a pouch-shaped case made of an aluminum laminate sheet. The electrode assembly, which is mounted in the battery case, is a power generating element that includes a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode and that can be charged and discharged. The electrode assembly is classified as a jelly-roll type electrode assembly, which is configured to have a structure in which a long sheet type positive electrode and a long sheet type negative electrode, to which active materials are applied, are wound in the state in which a separator is disposed between the positive electrode and the negative electrode, or a stacked type electrode assembly, which is configured to have a structure in which a plurality of positive electrodes having a predetermined size and a plurality of negative electrodes having a predetermined size are sequentially stacked in the state in which separators are disposed respectively between the positive electrodes and the negative electrodes.
Meanwhile, one of the most important factors in producing secondary batteries is quality control to determine whether secondary batteries exhibit desired performance and safety. Quality control is determining whether secondary batteries exhibit normal charge and discharge performance to sort good products from defective products. High-quality secondary batteries may be manufactured through such quality control.
In most cases, a worker manually tests the quality of battery packs in the state in which the battery packs are loaded on a jig in a workshop. In the case in which the worker manually tests the functions of the battery packs, however, the possibility of the battery pack being defective is increased due to errors in manual work or worker's mistakes, which leads to a reduction in production efficiency of the battery packs.
Therefore, there is a high necessity for a battery pack function test device that is capable of effectively testing the functions of battery packs through an automated process, thereby reducing the defect rate of the battery packs and thus greatly improving efficiency in production of the battery pack.